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Sansui QR-6500

Roypercy

Roypercy

Super Member
Hi all:

I've got a chance to purchase a QR-6500 receiver in excellent physical and working shape. Can anyone tell me about this receiver (wpc, etc.) Any thoughts about its quality? I love Sansui stuff and am intrigued by the cosmetics (and the size) of this unit, but I have no plan to "go quadrophonic". How well will it work as a stereo unit? I really know nothing about quad receivers, so any info you can give me would be helpful.

Thanks

Royston
 
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The man you should send a message to for the Info is AK Member, Quad Bob. There is also a website devoted to Quad that he participates in, I dont recall the exact link for it at the moment, but I'm sure QB can direct you to it. The 6500 is an early 70's model, it came out before the later QRX-7001, 8001, 9001 models.

B/F
 
Fellow Brooklynite:

I have the same receiver. Sounds really nice. Great amp. Great F.M. and A.M.. Accurate phone section.
Do not pay much attention to the power output ratings, because it is probably much higher than what is in the manual.
60 wpc rms into 4 ohms (times four)
37 into 8 ohms.
Super reliable Sansui stuff.
Never try to bridge outputs, to double the power when using the receiver for stereo. It is not made for this.:yippy: :yippy: :yippy:
 
bump - I just got one of these - now what???

Thought I'd resurrect an old thread instead of starting a new one....

Had an 'itch' to take an early lunch and check out the thrifts - scored a Sansui QR 6500! :banana: Heavy beast! Lit up at the store, but no way to test it. Bought it anyway, based on it that it looks to be pretty high quality, and it's a Sansui! Love the looks of it, but the cabinet is painted black, and the face has some scratches (too many really - how do faces get so stratched up???)

Of course, I don't even know if it actually works - the two fuses for the rear speakers are blown :worried: , but the fronts are intact. A slow process of checking it out will happen tonight, one channel at a time, checking DC offset before attaching a speaker.

However, to get ahead of myself here.....I've been digging through the archives for info on it. OK, so do not bridge the outputs, but what about running them in parallel? Connect the front and rear grounds, and positives and run them to a pair of stereo speakers??? Just a question - I won't actually do this, unless it really is OK to do. Not sure what the tone controls would think of it. OR, seperate the pre-main, and use an active crossover to biamp some 2-way speakers??

So, if it works, how can this be used to it's fullest as a stereo only amp??
 
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Either bi-amp, or get two pairs of similar speakers to do 4-channel. Didn't I already tell the other poster to never bridge the outputs?
Too bad that it looks like a bomb hit it, as it can be a good-looking machine. Mine has been ultra-reliable, but for some dial lights that were replaced when Jimmy Carter was president. Also, the dial cords (there are two), sometimes slip. Do not try to tighten. Perhaps some talc would work.

Seth
Forever Analog
 
Qr-6500

I bought a QR-6500 in 1973 and recently sold it. It is/was a superb sounding receiver and tone control allows tailoring for almost anyone’s tastes. The only problem it ever developed was a little dial cord slipping and there is a Sansui tech note on fixing that. From a quad point of view it was not as full featured as some of its successors but as a stereo unit you can’t go wrong on aesthetics, reliability and build quality.

sui-san
 
qr6500

Hey Suisan...how do I get to that service note to fix the slipping dial string?
I have 2 of these wonderful beasts, and both exhibit the same issue, I was about to try the beeswax method another member suggests, and by the way thx Mike for the beeswax...was also considering another tensioner similar in design to what is found in a r50 or t80 Sansui.
Slippage seems to be at the lower freqs end {left} side of the tuning scale.
Casey :scratch2:
 
NoTransistors said:
Either bi-amp, or get two pairs of similar speakers to do 4-channel. Didn't I already tell the other poster to never bridge the outputs?
Too bad that it looks like a bomb hit it, as it can be a good-looking machine. Mine has been ultra-reliable, but for some dial lights that were replaced when Jimmy Carter was president. Also, the dial cords (there are two), sometimes slip. Do not try to tighten. Perhaps some talc would work.

Seth
Forever Analog
Click to expand...

Seth, Thanks for the advice! I didn't realize that when you said don't bridge them, you were talking about what I described. I thought you were referring to bridging the way some pro-amps do it to get double the voltage swing to the speaker. Probably not possible with it anyways...

Cleaned it up - looks better with the dirt off. Scratches are not as noticable indoors under incandescent bulbs, and luckily all a the lettering is good. It is a nice looking receiver! I can't believe all the knobs are a) solid aluminum! and b) held on with 2 set screws each! 30 years ago some assembly line in Japan had people putting these knobs on with little jewelers screw drivers, one by one...

So, it works on the front channels, with headphones. Tuner sounds great. When I swap the 2 good fuses to the rear channels - no sound at all with head phones plugged into the rear jack :thumbsdn: but I still get sound from the front jack (no fuses in the front speakers fuse holders when doing this) - strange?. Russeled up one spare speaker to test, and same thing, only the fronts work. oh well...
Testing will continue later...

Looked inside for fuses (none) and black burnt bits (none). Huge power transformer. Funny thing is all the output transistors are the same (Toshibas) - aren't there supposed to be NPN and PNP types in pairs with different part numbers? Dial string is still OK with no slipping, but it does creak a bit in spots.

Anyway, thanks for the advice and comments. I'll try a pic or two tomorrow.
 
Have you cleaned the switches and pots? Thats where to start. Also, wiggle any connectors on the boards to be sure they are making good contact. As far as the type of output transistors, it depends on the amp design. Some use all one type others use NPN/PNP pairs.

- Pete
 
I also have one of these and it's an awesome amp. I love it. Enjoy it!
Oh, and ALWAYS make sure the volume knob didn't get turned up before you turn it on--these are powerful beasts! (yes, I still have my hearing...)
 
pre-out main-in!!!

finally had some time to get back to this and see what's wrong with it, when I'm looking at the connections at the back and, duh...I didn't notice that rear channels also had preout-main in RCA jacks, without the connectors! Plug some interconnects in, and it works on the rears too! I was so focused on the blown fuses in the rear channels that it didn't even dawn on me to look for the obvious! I am so pleased with this receiver - I've never had a Sansui from this period, and it makes me want to see what an 8080 or 9090, or even an earlier 30 to 50 wpc stereo receiver is like! I still needs the sliders cleaned (remove the face to get at them?) and one light behind the tuner scale (which I'm leaving as-is).

Here are some pics - notice how the cosmetics are different depending on if the flash was used, or room lighting with a long exposure and tripod.
 
Whenever I clean/lube rotary pots, they come out nice. These are the first sliders I ever cleaned/lubed (about 15 years ago), and it seems that the spray removed some lube that needs to stay. Even though they are quiet, they no longer slide smoothly. Same thing happened in a Panasonic receiver I cleaned last year. If the slider pots are quiet, then leave them alone.

Seth
Forever Analog
 
Hi,

I have a QR-5500 which is the same receiver, only less output. It was so clean when I got it, it looked like it was new. I did not get a case because it was part of a custom built inwall system. I have several problems with it that I could use some help on. It does not work with the decoder switch in the stereo mode. However if you switch to any of the quad posistions on the decoder switch it works. However the sound level of the left channel is about 40% less than the right, both front and rear. I have seen several others at estate sales and they all had the same problem when I tested them. Is there some design defect with them? I tried cleaning everything but no change. Right now it is being used as power amp connected to my 5000x because it has one channel of the anp section out,to drive 4 speakers. The problem is in the preamp section of the QR-5500 because using it as a power amp their is no level difference between the right and left channels. TIA.
 
These QR-XXXX amps seem to be a good buy used. I would expect 2x the number of caps. Has anyone performed cap replacement and/or an any circuit updates????


I thinking about geting a quad amp for stereo use and selling my 7070 and 8080db.
 
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